10 of the best droughtproof plants

Telegraph

2 days ago

The past few weeks have been a bit of a learning curve, because we've had an extremely dry spring followed by the warmest, driest June since 1976.
It's both impossible, and irresponsible, to water the entire garden, so I've concentrated on the containers, the greenhouses and any new additions showing signs of distress.
Everything else is taking its chance. My phloxes have flagged, my Veronicastrums look miserably hunched and my monardas aren't going to flower for me this year.
However, there are positives too. Certain plants have gloried in the dry heat and they're keeping my garden going. Given that drought and heat are likely to arrive more often, I'll be planting more of the following drought-busters.
Eryngiums, or sea hollies
The sea hollies have been my star performers and Eryngium x zabelii 'Big Blue' is the best of the lot.
The blue-rinsed sea-green elongated thimbles are supported by a ring of feathery bracts in aquamarine and the stiff stems have a steely sheen, so this is an architectural plant with presence.
The supporting foliage is jagged and marbled. One plant has produced a hundred or so stems, each topped with a splayed arrangement containing three to five pollinator-friendly flowers.
With no rain, the bracts and flowers have kept their metallic sparkle and I've watched several butterflies, including a marbled white, gathering nectar. Hundreds of bumblebees have been drooling over them too.
'Big Blue' is a micro-propagated hybrid, so seedlings don't come true to type. Here, it domineers a pallid-yellow anthemis, 'Sauce Hollandaise', and that's also enjoying the heat.
Eryngium bourgatii is self-seedling in nooks and crannies nearby and this one has silvered evergreen foliage.
Hylotelephiums, or sedums
Sedums have succulent leaves that store water, so once established, they perform brilliantly in dry summers. The darker the foliage, the better for me, because they light up silvery planting.
'José Aubergine', named after Flemish nurseryman José De Buck, smoulders from the off. The aubergine-black foliage and upright stems are topped with domed heads of red-pink flowers that fade to chocolate-brown as autumn descends.
I also rate Ernst Pagels's 'Karfunkelstein', which is more smoky rhubarb, and the stately 'Matrona'. The latter produces pigeon-breast foliage that shimmers between pink and grey. None flag, however hot the weather.
Hemerocallis, or daylilies
These have Asian heritage and they love the warmth and heat, even when it's humid. They are mega-hardy too, so they are grown all over the world.
Admittedly, they sometimes sulk in dull summers in my high-altitude garden, but this year they've been worth their weight in gold.
There are thousands on offer, but I am going to extol the virtues of two elegant British-bred daylilies from the 1960s, because I'm not keen on the thicker-petalled bicoloured American ones.
The readily available lucid-yellow 'Whichford' has a cool hint of green in each flower. 'Red Precious' (sold by Norwell Nurseries) is a later tomato-red, a colour that flatters the mid-green strappy foliage.
I like the oranges too: 'Flasher', 'Mauna Loa' and 'Primal Scream' are being framed by a pale-blue catmint and scabious, and they're all basking in the heat. You will need to remove the unsightly spent flowers, but the strappy foliage will march on.
Mallows, including malvas and altheas
Many years ago, staff at Cambridge's Botanic Garden did a bee count and discovered that Malva moschata was the number-one choice.
Mine self-seeds (which I don't mind) and most have a cluster of silky white saucers, softened by a pink style, above highly divided green foliage that avoids transpiration.
This is native to southern England, but it's also found in a wide area of Asia and Europe. I also grow the willowy light-pink Althaea armeniaca for its August flowers.
Stipa gigantea – the golden oat grass
One of the very few tall grasses to perform early in the year, this is indispensable in sunny borders because it produces a multitude of upright stems topped with shimmering golden heads. It loves the heat and I've found it long-lived.
Here, it rises to 5ft or more, hovering above an excellent rose for poorer soil, 'Bonica', which was raised in southern France.
My ramrod-straight spires of pink chicory (Cichorium intybus f. roseum), their neat daisies held on 45-degree-angled stems, are nearly as tall as the stipa this year. One note of caution though: stipas hate being divided or moved.
Origanum, or marjoram
Aromatic plants produce their own oily sunscreen and their flowers produce highly concentrated nectar, so they are all butterfly magnets.
Origanum laevigatum 'Herrenhausen' has delicate heads of small pink flowers, held in almost purple calices, and they bob above a mat of dark-green foliage.
Origanum laevigatum is native to Cyprus, Syria and Turkey, so it's more than capable of taking the heat. Thymes and all origanums are equally good at soaking up the sun in garden hotspots, without wilting.
Penstemons
These North American plants are bred from species used to being baked in the wild and they come into their own as the days shorten, because they're native to areas close to the equator, where days and nights are evenly balanced.
The wine-red ' Andenken an Friedrich Hahn ' has slender trumpets and fine foliage and it's one of the hardiest and showiest, flowering right up until November if deadheaded. 'Sour Grapes', a dusky purple, is almost luminous in the evening light here. 'Blackbird' and 'Czar' are darker options.
Go for fully grown plants at this time of year; try Hayloft (hayloft.co.uk).
Asters
Italian asters, named forms of Aster amellus, have long-lashed petals, so they're perfect for the front of a sunny border.
'Veilchenkönigin', which translates as 'Violet Queen', is the darkest of all. 'King George' is a lighter violet-purple and both are really good AGM (RHS Award of Garden Merit) plants.
The best drought-busting aster of all is a vigorous Swiss hybrid from the 1920s, named A x frikartii ' Mönch'. It swoons a little, reaching between 2ft and 3ft, and flowers for at least two months, and the foliage stays looking good too.
Phlomis
These Mediterranean plants have strong square-sided stems decorated with rounded whorls of lipped flowers. The flowers are adored by bumblebees and, after pollination, good seedheads endure until winter. Hibernating insects find the nooks and crannies very useful over winter.
Phlomis italica, the pink-flowered Balearic Island sage, has risen to a metre here and formed a substantial bush of pale, woolly foliage in a sunny well-drained position. This one's fully evergreen, so it can look fabulous in winter light when the leaves appear quilted.
The more stately Phlomis russeliana is a spreading herbaceous perennial, with stout stems containing five whorls of pallid-yellow flowers supported by mid-green foliage. This substantial phlomis, found naturally in Syria, Turkey and south-west Asia, needs a bit of space.
Scabiosa – the small scabious
One of my mainstays is the small scabious, Scabiosa columbaria, which is a chalk or lime grassland plant native to the UK, among other places. It's easily grown from seed and the standard form has pale-blue flowers.
There is also a pallid-yellow subspecies named ochroleuca, and both bear small pincushions on very wiry stems, above finely cut foliage. This scabious is totally reliable, performing in good and poor summers.
It's universally popular with butterflies and bees and mine forms a delicate edge in front of orange and orange-red hemerocallis and crocosmias. Deadheading will keep it going for weeks and I'd line every path with it if I could.